1. Field of the Invention
The present invention relates generally to an apparatus for a printer and/or copier device and, in particular, to a burn-in station apparatus that can be coupled to the printer and/or copier device. The invention is also directed to a printer and/or copier device having a printing unit that generates a latent image, develops it with toner and transfer-prints the developed toner image onto a carrier material. A fixing unit that fixes the transfer-printed toner image on the carrier material is arranged in the printer and/or copier device. The invention is also directed to a method for printing a carrier material.
2. Description of the Related Art
Many printers and copiers use toner to generate an image on a carrier material, such as paper. The toner must be fixed on the carrier to ensure that it does not rub off. A high quality and durable fixing of the toner image on the carrier is increasingly expected from modern electrographic printer and/or copier systems. Specifically, the dry toners employed in electrophotography contain mainly meltable synthetic resins that melt when heat is applied. Depending on the fixing method, the thermal energy is transmitted onto the toner and onto the paper either by radiation, for example using a photoflash or infrared radiation fixing, or by thermal contact, for example using hot rolling or trans-fixing (intermediate image transfer and fixing).
European patent application EP 0 789 860 B1 has disclosed a multi-functional electrographic printer device for single-sided or both-sided printing of recording media in a start-stop mode. This patent application as well as the corresponding U.S. Pat. No. 5,713,071 are hereby incorporated by reference into the present specification.
The electrographic printer devices disclosed in these patent applications have two fixing stations. The first fixing station fixes the toner image which has been transfer-printed onto the front side of the carrier material, and the second fixing station fixes the toner image which has been transfer-printed onto the back side of the carrier material. The fixing thereby ensues with a thermal printing fixing station having a heated fixing drum and an appertaining pressure drum. The possibility of fashioning the thermal printing fixing station with a heated or unheated admission saddle is also disclosed. The possibility of fixing the image with the assistance of a photoflash fixing device as well as with the assistance of a cold fixing device is also disclosed in these patent applications.
In order to achieve a high coincidence of the position of the print images on the front side and back side in duplex printing, it must be assured that there is only a slight change in size of the carrier material, for example of the paper, when fixing the image on the first transfer-printed side, for example the front side, of the carrier material. Fixing of the toner image onto the paper results in moisture being removed from the paper due to the thermal influence of the fixing operation, so that the paper shrinks. When the second toner image is subsequently transferred onto the other side of the paper, for example onto the back side, there occurs a size difference of the print images due to the shrinkage which is temperature dependent. The paper is stressed due to the thermal influence during fixing. The heat application must be reduced in order to keep the stress on the paper low, i.e. in order to reduce the shrinkage of the paper. However, enough heat must be supplied so that the toner of the transfer-printed toner image melts and is thus fixed.
Low melting temperatures are an aim in recent developments of toners in order to be able to reduce the heat application when fixing the toner on the carrier material.
It is necessary to limit the temperature influence on the carrier material and to achieve a qualitatively high-grade fixing at the same time, particularly when generating printed products having enhanced demands such as are required to protect against counterfeiting, in what is referred to as security printing. In order to assure a durable adhesion of the fixed toner on the carrier material, it is necessary that so much energy be supplied to the toner that it becomes fluid in order to penetrate into the carrier material.
When printing self-adhesive labels and carrier material that contains integrated circuits, it is also necessary to keep the amount of heat transferred onto the carrier material low.
The following documents are referenced as further Prior Art: U.S. Pat. No. 5,983,064; U.S. Pat. No. 5,392,096; German Patent document DE 35 01 303 A1; German Patent document DE 32 21 059 A1; U.S. Pat. No. 4,634,257; Xerox Disclosure Journal, 17, No. 4, pp. 223-224; Published PCT International Application WO 98/27466; German Patent document DE 40 36 975 A1; European Patent document EP 0 107 722 B1; British Patent document GB 2 110 597 A; European Patent document EP 0 034 817 A2; German Patent document DE 21 30 891 A1; Published PCT International Application WO 98/39691; and German Patent document DE 197 09 504 A1.
Published PCT International Application WO98/39691 discloses a printer or copier device for performance-adapted printing of a recording medium. The printer or copier device contains a modularly arranged fixing unit. Japanese Letters Patent JP 57201273 discloses an arrangement for fixing toner images on a carrier material. A photoflash fixing unit that is controlled dependent on the properties of the carrier material is utilized for fixing. The document “TWO STEP FUSING PROCESS AND ACCESSORY FOR LASER PRINTERS” IBM TECHNICAL DISCLOSURE BULLETIN, IBM CORP. NEW YORK, US, Vol. 40, No. 8, 1 Aug. 1997 (1997-08-01), pages 23-25, XP000735565 ISSN: 0018-8689 discloses that a drum fixing and a radiant fixing be successively implemented in order to fix a toner image on a carrier material in a laser printer. Japanese Letters Patent JP 60252380 A discloses a pressing and hot-fixing unit for fixing toner images on a carrier material. The control of the pressing and hot-fixing unit ensues dependent on properties of the carrier material.